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  <div class="section" id="numpy-isneginf">
<h1>numpy.isneginf<a class="headerlink" href="#numpy-isneginf" title="Permalink to this headline">¶</a></h1>
<dl class="function">
<dt id="numpy.isneginf">
<code class="sig-prename descclassname">numpy.</code><code class="sig-name descname">isneginf</code><span class="sig-paren">(</span><em class="sig-param">x</em>, <em class="sig-param">out=None</em><span class="sig-paren">)</span><a class="reference external" href="https://github.com/numpy/numpy/blob/v1.18.1/numpy/lib/ufunclike.py#L191-L258"><span class="viewcode-link">[source]</span></a><a class="headerlink" href="#numpy.isneginf" title="Permalink to this definition">¶</a></dt>
<dd><p>Test element-wise for negative infinity, return result as bool array.</p>
<dl class="field-list">
<dt class="field-odd">Parameters</dt>
<dd class="field-odd"><dl class="simple">
<dt><strong>x</strong><span class="classifier">array_like</span></dt><dd><p>The input array.</p>
</dd>
<dt><strong>out</strong><span class="classifier">array_like, optional</span></dt><dd><p>A boolean array with the same shape and type as <em class="xref py py-obj">x</em> to store the
result.</p>
</dd>
</dl>
</dd>
<dt class="field-even">Returns</dt>
<dd class="field-even"><dl>
<dt><strong>out</strong><span class="classifier">ndarray</span></dt><dd><p>A boolean array with the same dimensions as the input.
If second argument is not supplied then a numpy boolean array is
returned with values True where the corresponding element of the
input is negative infinity and values False where the element of
the input is not negative infinity.</p>
<p>If a second argument is supplied the result is stored there. If the
type of that array is a numeric type the result is represented as
zeros and ones, if the type is boolean then as False and True. The
return value <em class="xref py py-obj">out</em> is then a reference to that array.</p>
</dd>
</dl>
</dd>
</dl>
<div class="admonition seealso">
<p class="admonition-title">See also</p>
<p><a class="reference internal" href="numpy.isinf.html#numpy.isinf" title="numpy.isinf"><code class="xref py py-obj docutils literal notranslate"><span class="pre">isinf</span></code></a>, <a class="reference internal" href="numpy.isposinf.html#numpy.isposinf" title="numpy.isposinf"><code class="xref py py-obj docutils literal notranslate"><span class="pre">isposinf</span></code></a>, <a class="reference internal" href="numpy.isnan.html#numpy.isnan" title="numpy.isnan"><code class="xref py py-obj docutils literal notranslate"><span class="pre">isnan</span></code></a>, <a class="reference internal" href="numpy.isfinite.html#numpy.isfinite" title="numpy.isfinite"><code class="xref py py-obj docutils literal notranslate"><span class="pre">isfinite</span></code></a></p>
</div>
<p class="rubric">Notes</p>
<p>NumPy uses the IEEE Standard for Binary Floating-Point for Arithmetic
(IEEE 754).</p>
<p>Errors result if the second argument is also supplied when x is a scalar
input, if first and second arguments have different shapes, or if the
first argument has complex values.</p>
<p class="rubric">Examples</p>
<div class="doctest highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">np</span><span class="o">.</span><span class="n">isneginf</span><span class="p">(</span><span class="n">np</span><span class="o">.</span><span class="n">NINF</span><span class="p">)</span>
<span class="go">True</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">np</span><span class="o">.</span><span class="n">isneginf</span><span class="p">(</span><span class="n">np</span><span class="o">.</span><span class="n">inf</span><span class="p">)</span>
<span class="go">False</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">np</span><span class="o">.</span><span class="n">isneginf</span><span class="p">(</span><span class="n">np</span><span class="o">.</span><span class="n">PINF</span><span class="p">)</span>
<span class="go">False</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">np</span><span class="o">.</span><span class="n">isneginf</span><span class="p">([</span><span class="o">-</span><span class="n">np</span><span class="o">.</span><span class="n">inf</span><span class="p">,</span> <span class="mf">0.</span><span class="p">,</span> <span class="n">np</span><span class="o">.</span><span class="n">inf</span><span class="p">])</span>
<span class="go">array([ True, False, False])</span>
</pre></div>
</div>
<div class="doctest highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">x</span> <span class="o">=</span> <span class="n">np</span><span class="o">.</span><span class="n">array</span><span class="p">([</span><span class="o">-</span><span class="n">np</span><span class="o">.</span><span class="n">inf</span><span class="p">,</span> <span class="mf">0.</span><span class="p">,</span> <span class="n">np</span><span class="o">.</span><span class="n">inf</span><span class="p">])</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">y</span> <span class="o">=</span> <span class="n">np</span><span class="o">.</span><span class="n">array</span><span class="p">([</span><span class="mi">2</span><span class="p">,</span> <span class="mi">2</span><span class="p">,</span> <span class="mi">2</span><span class="p">])</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">np</span><span class="o">.</span><span class="n">isneginf</span><span class="p">(</span><span class="n">x</span><span class="p">,</span> <span class="n">y</span><span class="p">)</span>
<span class="go">array([1, 0, 0])</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">y</span>
<span class="go">array([1, 0, 0])</span>
</pre></div>
</div>
</dd></dl>

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